The present invention relates in general to bulk material containers, and more particularly to a bulk material container with a flexible liner.
Heretofore, the shell of a bulk material container had a flexible liner installed therein. At the bottom of the flexible liner was an opening, which received a tubular outlet fitting. The tubular outlet fitting of the flexible liner was inserted through a suitable opening at the bottom of the shell of the bulk material container. An outlet conduit was connected to the tubular outlet fitting externally of the shell. By using a combination of expansion of the tubular outlet fitting and compression of the discharge edge of the tubular outlet fitting, a seal was provided between the flexible liner and the outlet conduit. This was a single seal relying on both diameter and length clearances to maintain a fixed dimension and thus a seal. Material, such as polyethylene, is known to flow under pressure, and conceivably could lose the effect of a single seal. Thus, heretofore there was a lack of certainty that the tubular outlet fitting of the flexible liner was properly positioned to receive the outlet conduit which locked the tubular outlet fitting of the flexible liner into position. Hence, the extent of the seal was uncertain.
In the U.S. patent to Nittel, U.S. Pat. No. 4,586,628, issued on May 6, 1986, for Resilient Inner Liner For Lining of Transport Or Storage Containers, there is disclosed a liner for a container. The liner is installed through a bottom opening of the container. A string or wire is fastened at the upper end of the liner to pull the liner to an upper opening of the container. A feed pipe is bonded to the lower end of the liner. A lower flange on the feed pipe abuts against the wall defining the opening at the lower end of the container.
The U.S. patent to Oswalt et al., U.S. Pat. No. 4,165,024, issued on Aug. 21, 1979, for Bulk Shipping Container, discloses a container with a liner. The liner has an opening at the bottom wall thereof. A draw and flow valve assembly includes a sealing nut that is disposed at the end of a draw conduit. The sealing nut causes a sealing ring to seal the wall surrounding the bottom opening of the liner to the valve assembly for the passage of bulk material. The container is filled with bulk material, or the bulk material can be discharged, through the bottom opening of the liner.
The U.S. patent to Mockesch, U.S. Pat. No. 4,256,150, issued on Mar. 17, 1981, for Method of Filling A Plastic Bag In A Pressure Tank With A Carbonated Beverage, In Particular Beer, discloses a spherical container open at the top thereof and at the bottom thereof. A liner is closed at the top and is opened at the bottom thereof. A ring, which forms the open bottom end of the liner, is seated in the opening at the bottom of the container. Beer is introduced into and removed from the opening at the bottom of the container and is introduced into and removed from the opening at the bottom of the liner. The liner is dropped into the container through the top opening of the container. The bottom opening of the liner is retained at the bottom opening of the container.